Blue mussel (Mytilus edulis) beds

These small, blue mussels are a common sight
on UK coasts. They can form extensive beds, with living and
dead mussels, sand and mud all bound together by the mussels’
sticky ‘beards’ of byssus threads. Blue mussel beds occur
mostly on the lower shore between the tides or permanently
submerged in shallow water.

Mussel beds provide an important food source
for wintering waders. When beds were lost from parts of Holland in
1990, the eider duck numbers decline significantly. Otters
may also get some of their food supply from blue mussel beds, and
the ‘mussel mud’ formed by the blue mussels’ waste is an important
source of nutrients for animals living within the seabed.

Blue mussel beds have a particularly
important role where they occur on soft seabeds, as they provide a
hard surface in otherwise muddy or sandy areas. This attracts
and supports a greater range of marine life than would otherwise be
found there including seaweeds, anemones, barnacles, sea
snails, crabs, starfish and worms.

The threats to blue mussel beds include
their removal for food or bait, and the damage caused by mobile
fishing gear, anchoring or mooring chains, or, for beds found
between the tides, by trampling. They are also at risk from
shoreline building developments, dredging, and pollution.

Blue mussel beds take at least five years to
recover from damage, and those in southern England are some of the
most threatened in Europe.

For the official habitat definition please see
the documents listed below.

European distribution

Blue mussels are widespread on the shore and
in shallow water around the coasts of the UK and Europe.
Significant beds of blue mussels on soft sea beds are found in
scattered locations within this broad range.